only set I2C jumpers JC2, JC3, JC4, JC5, JC6, JC7 (at the top) if there is a corresponding I2C module installed

set jumper JP8 to 'Always-ON' for tests and for Arduino uploads, for regular operation (and automatic undervoltage power-off) to 'Automatic'

unset jumper JP3 (2nd mower motor MC33926 M1FB), not used

Solder a bridge on leftmost pins of S1 ODO right and S2 ODO left (PCB back side)

RTC module must be installed for proper I2C bus operation

press button P20 to power-on PCB

Assembly

Soldering the mainboard components

Front view of an empty mainboard v1.3

The assembly of the board is tricky as some components have been packed tightly - especially those below the motor drivers.

The following table lists each component to be placed by hand along with other components that might collide. Collisions marked with a '?' are hard (but still possible) to solder if the components are not placed in the right order. Those without a '?' are impossible. The table has been sorted to provide a practical order for soldering: low components come first and components blocking each other are in the right order. Similar components and spatiality has been used to form groups.

Component

Can be blocked by

Can block

Profile

Comment

JP3

P22, P4

low

SMD

F1

JP1?, C1?

low

SMD

S1

low

solder a small lead as bridge

S2

low

solder a small lead as bridge

S3

low

solder a small lead as bridge

C2

low (lying)

C3

low (lying)

C9

low

Wasn‘t included. Maybe optional?

C12

low (lying)

D10

K3

low

I2C1

low

connector socket

I2C2

low

connector socket

I2C3

low

connector socket

I2C4

low

connector socket

I2C5

low

connector socket

I2C6

low

connector socket

I2C7

low

connector socket

P1

C11?

low

connector socket

P2

C11?

low

connector socket

P3

low

connector socket

P4

JP3

low

connector socket

P5

low

connector socket

P6

low

connector socket

P8

SP1

SP1?

low

connector socket

P9

low

connector socket

P11

low

connector socket

P12

low

connector socket

P13

low

connector socket

P14

low

connector socket

P19

C11?

low

connector socket

P20

C10?

low

connector socket

P21

C11?

low

connector socket

P22

JP3

low

connector socket

P23

low

connector socket

P25

low

connector socket

P26

low

connector socket

P27

low

connector socket

P28

low

connector socket

P30

low

connector socket

P31

C10?

low

connector socket

P35

low

connector socket

P40

low

connector socket

P41

C11?

low

connector socket

P44

low

connector socket

P46

SP1, C11?

SP1?

low

connector socket

P48

low

connector socket

P7

low

socket

P10

low

socket

U1

low

socket

U2

low

socket

U3

C10?

low

socket

U8RTC

low

socket?

U11

low

socket

JC2

mid

pins

JC3

mid

pins

JC4

mid

pins

JC5

mid

pins

JC6

mid

pins

JC7

mid

pins

JP1

F1?

mid

pins

JP2

mid

pins

JP4

mid

pins

JP5

mid

pins

JP6

mid

pins

JP7

mid

pins

JP8

mid

pins

JP9

mid

pins

JP10

mid

pins

JP11

mid

pins

JP12

mid

pins

JP13

mid

pins

P24

mid

pins

P29

mid

pins

P32

mid

pins

P33

mid

pins

P34

mid

pins

P38

mid

pins

P45

mid

pins

P47

mid

pins

P50

mid

pins

P51

mid

pins

BY1

PRFA2?

RL1?

low

BY4

PRFA2?

low

BY7

CC2?

low

DKE1

CC2, RL2?

low

BY8

CC2, RL2?

low

BY9

PRFA1?, C10?

low

BY10

PRFA1?, CC3, RL3?

CC3?

low

place in a raised position

RL3

C10, BY2, BY11, PRFA1?

BY2?, BY10?, BY12?

low

PRFA2

RL1, C11?

BY1?, BY3?, BY4?

low (lying)

lay down later

RL1

BY3, DKE2, BY1?, C11?

PRFA2

low

BY3

PRFA2?

RL1

low

PRFA1

RL2

RL2?, RL3?, BY9?, BY10?, BY12?, C10?, EF3?

low (lying)

lay down later

RL2

P49, BY6, BY5, PRFA1?

BY8?, DKE1?, PRFA1

low

EF3

PRFA1?, CC3

CC3

low

Conflict CC3

CC3

EF3, BY12, BY10?

EF3, BY10

high

Conflict EF3

BY2

C11?, RL3?

RL3

low

BY5

CC2?

RL2

low

BY6

P49

RL2

low

BY12

RL3?, PRFA1?

CC3

low

BY11

C11?

RL3

low

DKE2

C11?

RL1

low

Dual1

C10

C10?

low

socket; solder the sockets near the screw connectors later

Dual2

C11

C11?

low

socket; solder the sockets near the screw connectors later

K3

D10

mid

relais socket

Due

C10?

high

high pins; insert them into the Due-board first and then place them alltogether into the mainboard for soldering

Soldering the Voltage regulator

Just insert four 1-pins into the corners. It's pretty easy if you insert the module into the main board while soldering.

Voltage regulator front view

Voltage regulator back view

Unplug the regulator and connect a +24 V voltage source to the inputs and a multimeter to the outputs (measure DC voltage). Adjust the output voltage to 9 V using the screw on top of the potentiometer.

Voltage regulator calibration using a multimeter

Plug the voltage regulator into the PCB and make sure the orientation is right!

Voltage regulator placed on the PCB 1.3

Soldering the RTC

Just insert a 5- and a 7-pin-row into the module. It's pretty easy if you insert the module into the main board while soldering.

RTC front view

RTC back view

Soldering the motor drivers

For each of the both drivers: Insert a row of 18 stacking pins (the longer ones) row into the mainboard. Insert 6 separated stacking pins into the mainboard. Try to put the module onto those pins and solder them.

Motor driver front view

Motor driver back view

Putting everything together

If you stick everything together, you have something that should look roughly like this: